Department of Biological Sciences. Purdue University, West Lafayette. Indiana 47906, USA.
Thermoregulation in Yersinia enterocolitica is coincident with changes in DNA supercoiling
Article first published online: 27 OCT 2006
Volume 12, Issue 2, pages 187–199, April 1994
How to Cite
Rohde, J. R., Fox, J. M. and Minnich, S. A. (1994), Thermoregulation in Yersinia enterocolitica is coincident with changes in DNA supercoiling. Molecular Microbiology, 12: 187–199. doi: 10.1111/j.1365-2958.1994.tb01008.x
- Issue published online: 27 OCT 2006
- Article first published online: 27 OCT 2006
- Received 2 June, 1993; revised 12 December, 1993; accepted 10 January, 1994.
Yersinia enterocolitica is a facultative intracellular parasite, displaying the ability to grow saprophytically or invade and persist intracellularly in the mammalian reticuloendothelial system. The transition between such diverse environments requires the co-ordinated regulation of specific sets of genes on both the chromosome and virulence plasmid. Temperature has a profound pleiotropic effect on gene expression and phenotypically promotes alterations in cell morphology, outer-membrane protein synthesis, urease production, lipopolysaccharide synthesis, motility, and synthesis of genes involved in invasion of euKaryotic host cells. By examining thermoregulated flagella biosynthesis, we have determined that motility is repressed at 25° C (permissive temperature) with subinhibitory concentrations of novobiocin. These conditions also induce virulence gene expression suggesting novobiocin addition stimulates, at least partially, a high-temperature environment. Furthermore, temperature-shift experiments, using Y. enterocolitica containing pACYC184 as a reporter plasmid, indicate that thermo-induced alterations of DNA supercoiling coincide with temperature-induced phenotypic changes. A class of putative DNA gyrase mutant (novobiocin resistant) likewise demonstrates the 37° C phenotype when cultured at 25°C; it is non-motile, urease negative, calcium growth dependent, and positive for Yop expression. These results support a model implicating DNA topology as a contributing factor of Y. enterocolitica thermoregulation.